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Systems, Volume 5, Issue 4 (December 2017) – 7 articles

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1632 KiB  
Article
Using Agent-Based Modeling to Assess Liquidity Mismatch in Open-End Bond Funds
by Donald J. Berndt, David Boogers, Saurav Chakraborty and James McCart
Systems 2017, 5(4), 54; https://doi.org/10.3390/systems5040054 - 6 Dec 2017
Cited by 2 | Viewed by 9486
Abstract
In this paper, we introduce a small-scale heterogeneous agent-based model of the US corporate bond market. The model includes a realistic micro-grounded ecology of investors that trade a set of bonds through dealers. Using the model, we simulate market dynamics that emerge from [...] Read more.
In this paper, we introduce a small-scale heterogeneous agent-based model of the US corporate bond market. The model includes a realistic micro-grounded ecology of investors that trade a set of bonds through dealers. Using the model, we simulate market dynamics that emerge from agent behaviors in response to basic exogenous factors (such as interest rate shocks) and the introduction of regulatory policies and constraints. A first experiment focuses on the liquidity transformation provided by mutual funds and investigates the conditions under which redemption-driven bond sales may trigger market instability. We simulate the effects of increasing mutual fund market shares in the presence of market-wide repricing of risk (in the form of a 100 basis point increase in the expected returns). The simulations highlight robust-yet-fragile aspects of the growing liquidity transformation provided by mutual funds, with an inflection point beyond which redemption-driven negative feedback loops trigger market instability. Full article
(This article belongs to the Special Issue Pervasive Simulation for Enhanced Decision Making)
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<p>US corporate bond market size. Source: SIFMA, data analysis by authors.</p>
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<p>The 30-year decline in 10-year Treasury yields. Source: Federal Reserve Economic Data (FRED) [<a href="#B3-systems-05-00054" class="html-bibr">3</a>].</p>
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<p>Average maturity of US corporate bonds (number of years). Source: Financial Times; SIFMA data.</p>
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<p>Investor ecosystem circa 1981 (Q1) by approximate market share. Source: Federal Reserve Flow of Funds data [<a href="#B6-systems-05-00054" class="html-bibr">6</a>], analysis by authors.</p>
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<p>Investor ecosystem circa 2016 (Q3) by approximate market share. Source: Federal Reserve Flow of Funds data [<a href="#B6-systems-05-00054" class="html-bibr">6</a>], analysis by authors.</p>
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<p>The financial system as a multilayer network. Source: Office of Financial Research [<a href="#B23-systems-05-00054" class="html-bibr">23</a>].</p>
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<p>The liquidity ladder. Source: Tabb Group.</p>
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<p>Bond price trends for a 15% mutual fund market share.</p>
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<p>Bond price trends for a 25% mutual fund market share.</p>
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<p>Bond price trends for a 35% mutual fund market share.</p>
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<p>Bond price trends for a 30% mutual fund market share.</p>
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6691 KiB  
Article
A Conceptual Design of Spatio-Temporal Agent-Based Model for Volcanic Evacuation
by Jumadi, Steve Carver and Duncan Quincey
Systems 2017, 5(4), 53; https://doi.org/10.3390/systems5040053 - 26 Nov 2017
Cited by 14 | Viewed by 10684
Abstract
The understanding of evacuation processes is important for improving the effectiveness of evacuation plans in the event of volcanic disasters. In terms of social processes, the enactment of evacuations in volcanic crises depends on the variability of individual/household responses. This variability of population [...] Read more.
The understanding of evacuation processes is important for improving the effectiveness of evacuation plans in the event of volcanic disasters. In terms of social processes, the enactment of evacuations in volcanic crises depends on the variability of individual/household responses. This variability of population response is related to the uncertainty and unpredictability of the hazard characteristics of volcanoes—specifically, the exact moment at which the eruption occurs (temporal), the magnitude of the eruption and which locations are impacted (spatial). In order to provide enhanced evacuation planning, it is important to recognise the potential problems that emerge during evacuation processes due to such variability. Evacuation simulations are one approach to understanding these processes. However, experimenting with volcanic evacuations in the real world is risky and challenging, and so an agent-based model is proposed to simulate volcanic evacuation. This paper highlights the literature gap for this topic and provides the conceptual design for a simulation using an agent-based model. As an implementation, an initial evacuation model is presented for Mount Merapi in Indonesia, together with potential applications of the model for supporting volcanic evacuation management, discussion of the initial outcomes and suggestions for future work. Full article
(This article belongs to the Special Issue Pervasive Simulation for Enhanced Decision Making)
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<p>Geographic Information System (GIS) and Agent-Based Model (ABM) interaction concept.</p>
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<p>Conceptual framework of agent and environment interaction.</p>
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<p>Hazard zonation for the area around Merapi [<a href="#B132-systems-05-00053" class="html-bibr">132</a>].</p>
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<p>The dynamic changes of hazard level of the zones during the simulation in two different scenarios [<a href="#B132-systems-05-00053" class="html-bibr">132</a>].</p>
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<p>Main agent (people) characteristics.</p>
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<p>Agents—environment mechanism and interaction flowchart.</p>
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<p>Screenshot of model implementation using AnyLogic. Red dots at (<b>A</b>) are the initial spatial distribution of people at risk. Grey dots are the people outside the danger zones. Subsequently, the people dots change to yellow with the increment of hazard levels at (<b>B</b>–<b>D</b>). The movements of people and the changing of the spatial distribution of individuals are displayed at (<b>B</b>–<b>D</b>). The monitor chart is (<b>a</b>) monitoring the simulated volcanic activity level; (<b>b</b>) monitoring the number of people at risk and (<b>c</b>) monitoring the percentage of people evacuating.</p>
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<p>Example of result analysis of people at risk in different time steps using GIS.</p>
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<p>Example of the simulation outcomes of various scenarios. VEI: volcanic explosivity index, CL: crisis length (days). This can be adjusted based on the preferred scenario. The scenario setup shows the length of each activity phase, which can be adjusted to match with the real crisis situations. The top chart shows that the percentage of people at risk is continuously decreasing along with the increase in the percentage of people evacuating.</p>
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<p>Example of the result of route density analysis.</p>
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<p>Example of the results of evacuee distribution simulations.</p>
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<p>Clearance time for various scenarios. VEI: volcanic explosivity index, CL: crisis length (days).</p>
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<p>Temporal dynamic of evacuees through the crisis period in 2010. (<b>a</b>) the issuance of the first evacuation order on 3 November 2010; (<b>b</b>) the issuance of the second evacuation order on 3 November 2010; (<b>c</b>) the issuance of the third evacuation order on 5 November 2010 (Source: Volcanic Crisis Chronology [<a href="#B4-systems-05-00053" class="html-bibr">4</a>] and Evacuation data [<a href="#B161-systems-05-00053" class="html-bibr">161</a>]).</p>
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<p>Comparison of the average simulation result (10 runs) with the real data for the 2010 evacuation. Note: the returning home process is excluded from this comparison.</p>
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7938 KiB  
Article
An Integral Model to Provide Reactive and Proactive Services in an Academic CSIRT Based on Business Intelligence
by Walter Fuertes, Francisco Reyes, Paúl Valladares, Freddy Tapia, Theofilos Toulkeridis and Ernesto Pérez
Systems 2017, 5(4), 52; https://doi.org/10.3390/systems5040052 - 23 Nov 2017
Cited by 10 | Viewed by 11917
Abstract
Cyber-attacks have increased in severity and complexity. That requires, that the CERT/CSIRT research and develops new security tools. Therefore, our study focuses on the design of an integral model based on Business Intelligence (BI), which provides reactive and proactive services in a CSIRT, [...] Read more.
Cyber-attacks have increased in severity and complexity. That requires, that the CERT/CSIRT research and develops new security tools. Therefore, our study focuses on the design of an integral model based on Business Intelligence (BI), which provides reactive and proactive services in a CSIRT, in order to alert and reduce any suspicious or malicious activity on information systems and data networks. To achieve this purpose, a solution has been assembled, that generates information stores, being compiled from a continuous network transmission of several internal and external sources of an organization. However, it contemplates a data warehouse, which is focused like a correlator of logs, being formed by the information of feeds with diverse formats. Furthermore, it analyzed attack detection and port scanning, obtained from sensors such as Snort and Passive Vulnerability Scanner, which are stored in a database, where the logs have been generated by the systems. With such inputs, we designed and implemented BI systems using the phases of the Ralph Kimball methodology, ETL and OLAP processes. In addition, a software application has been implemented using the SCRUM methodology, which allowed to link the obtained logs to the BI system for visualization in dynamic dashboards, with the purpose of generating early alerts and constructing complex queries using the user interface through objects structures. The results demonstrate, that this solution has generated early warnings based on the level of criticality and level of sensitivity of malware and vulnerabilities as well as monitoring efficiency, increasing the level of security of member institutions. Full article
(This article belongs to the Special Issue Pervasive Simulation for Enhanced Decision Making)
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<p>Illustration of the conceptual and methodological framework of this study, which reveals the foundations used to design and implement the BI system using the phases of the Ralph Kimball methodology, ETL and OLAP processes. In addition, a Web software application has been implemented using the SCRUM methodology.</p>
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<p>The Ralph Kimball Methodology Life Cycle assembled with the development of BI applications with Agile SCRUM. This illustrated combination details the different phases for the accurate process with which we have been able to streamline and establish a system being focused strictly on the needs of the CSIRT.</p>
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<p>The Dimensional Data Base. The dimensional model for BI establishes a star topology, which allows a correct relationship between the facts and its associated dimensions.</p>
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<p>(<b>a</b>) Although the PVS is a proprietary system, the deployment of information is limited. Therefore, the flat databases for the PVS system provide timely and relevant information for vulnerabilities and events in real time; (<b>b</b>) The database for Snort is composed of the most significant tables of the original non-relational model of the Barnyard2 system.</p>
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<p>Job for data warehouse Load. Pentaho’s data integration system allows a robust generation of processes that lead to consecutive jobs and transformations.</p>
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<p>The Dimensional Load Work, where the workflow is set for one run every 24 h.</p>
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<p>Transformation from a flat file. The filter of the transformation supports the elimination of data that are able to generate drawbacks in the data collection.</p>
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<p>Schematic illustration of the algorithm of the generation of a filter with possible control of transformation errors. Pentaho’s data integration tool allows the execution of shell scripts. For this case, the script has been programmed with regular expressions.</p>
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<p>Transformation from an enriched xml. Pentaho’s data integration tool allows to extract the information of an attribute or a specific node from an XML file. In addition, the comparative establishes a flag avoiding data redundancy.</p>
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<p>The data loading algorithm with defined time loop execution. Reports are set every 6 h with a repeated loop.</p>
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<p>Transformation for filter generation from a .txt file. Pentaho’s data integration tool allows to operate with the metadata of a document. This establishes the knowledge about the modification date of a certain document, hereby generating changes within the database.</p>
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<p>OLAP cubes, as adapted from Pentaho Analysis Services Architecture. Source: Adaptation from [<a href="#B14-systems-05-00052" class="html-bibr">14</a>]. OLAP cubes are based on the correct schematization of the database. In addition, they generate data by MDX and SQL.</p>
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<p>A schematic illustration of the proposal to generate scalability using Big Data techniques. The proposed system includes the use of Apache Storm to centralize the obtained information, streamlining the process in case of the appearance of scenarios which include a large amount of data. Therefore, lots of data may be stored, processed and relevant data obtained from it, which will subsequently be stored in a corresponding database.</p>
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<p>The Module One with the Proof of Concept. Module one has been focused on the general deployment of information, being daily updated.</p>
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<p>The proof of concept of module two. This module conceives the data management in real time. Therefore, the ETL processes capture a greater use of the resources for its continuous execution.</p>
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<p>(<b>a</b>) Most occurred events in 2016; (<b>b</b>) Total number of incidents per year.</p>
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<p>(<b>a</b>) Most delayed events to be solved; (<b>b</b>) Number of events by type.</p>
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<p>(<b>a</b>) Evaluation of events per day; (<b>b</b>) Evaluation type of event and frequency.</p>
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<p>(<b>a</b>) Evaluation of vulnerability per host; (<b>b</b>) Vulnerability assessment per day.</p>
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<p>(<b>a</b>) Number of events classified by level of criticality and sensitivity; (<b>b</b>) Bar illustration with the Total Evaluation of Risk.</p>
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<p>(<b>a</b>) Execution time in seconds of a SQL and a NoSQL database. This establishes the time that has been spent writing the files in a SQL and a NoSQL database; (<b>b</b>) Speed measured in registers per second of a SQL and a NoSQL database. This sets the speed at which files have been processed for a SQL and a NoSQL database.</p>
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2971 KiB  
Article
Social Systems: Resources and Strategies
by Pavel Brazhnikov
Systems 2017, 5(4), 51; https://doi.org/10.3390/systems5040051 - 15 Nov 2017
Cited by 2 | Viewed by 7464
Abstract
This theoretical article reviews the model describing processes in social systems based on the analysis of their resource base. Application of the system theory can help to explain why some systems are aimed at prevention of type I errors, while others seek to [...] Read more.
This theoretical article reviews the model describing processes in social systems based on the analysis of their resource base. Application of the system theory can help to explain why some systems are aimed at prevention of type I errors, while others seek to decrease the quantity of type II errors. Such differences are manifested in investment of resources either into deep interaction or into wide coverage. Some examples of such strategies in economic, market and production systems are provided in the article. The article introduces some provisions of the system theory in the context of the resource flows. The main indicators that are considered in this article are the characteristics of the sources of the exchanging flows of resources. Their relative frequency and quality are investigated; on the basis of which the most effective strategy of the system is derived; as a mechanism for redistribution of resources. The rigor of the system’s strategy depends on the magnitude of the difference in characteristics. It is explained how exactly it influences the exchange processes, that in reality systems do not interact simultaneously and one of the opposite resource flows is always delayed. It is shown how the system strategy depends on the risks linked with interactions. Also, there are grounds for the need to accumulate resources, including in the situation of their surplus. The model helps also explain shift of economic centers throughout history. Additionally, there is an analogy between systems strategies and the competitive strategies described by M. Porter and outsourcing versus integration. Full article
(This article belongs to the Special Issue Complex Adaptive Systems)
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<p>Relative characteristics of resources of systems.</p>
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<p>Relative characteristics of state systems.</p>
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<p>Relative characteristics of market systems.</p>
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<p>Relative characteristics of production systems.</p>
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1127 KiB  
Article
The Complementary Perspective of System of Systems in Collaboration, Integration, and Logistics: A Value-Chain Based Paradigm of Supply Chain Management
by Raed Jaradat, Frank Adams, Sawsan Abutabenjeh and Charles Keating
Systems 2017, 5(4), 50; https://doi.org/10.3390/systems5040050 - 20 Oct 2017
Cited by 20 | Viewed by 13716
Abstract
The importance and complexity of the problems associated with coordinating multiple organizations to configure value propositions for customers has drawn the attention of multiple disciplines. In an effort to clarify and consolidate terms, this conceptual research examines both supply chain management (SCM) and [...] Read more.
The importance and complexity of the problems associated with coordinating multiple organizations to configure value propositions for customers has drawn the attention of multiple disciplines. In an effort to clarify and consolidate terms, this conceptual research examines both supply chain management (SCM) and system of systems (SoS) literature to postulate, from a value-chain perspective, what roles integration and collaboration play in helping supply chains satisfy customer requirements. A literature review analysis was used to identify the commonalities and differences between supply chain management and system of systems approaches to examining interfirm coordination of value creation efforts. Although a framework of integration and collaboration roles in value creation is proposed, further empirical testing of the concept is required to substantiate initial conclusions. The concepts proposed may help clarify where strategic and operational managers need to focus their efforts in coordinating supply chain member firms. The incorporation of SoS engineering into the supply chain field will draw the linkage between the constituent principles, and concepts of Systems Theory as appropriate for the supply chain management field. This is the first effort to reconcile two separate but parallel scholarship streams examining the coordination of multiple organizations in value creation. This research shows that there are some methodologies, principles, and methods from the SoS field that can supplement supply chain management research. Mainly due to a unit of analysis issue, systems based approaches have not been in the mainstream of supply chain management field development. Full article
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<p>A conceptual hierarchy of supply chain management domains.</p>
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<p>Porter’s value chain.</p>
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<p>A value-chain view of supply chain collaboration.</p>
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<p>A value-chain view of supply chain external integration.</p>
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<p>The roles of collaboration, integration, and systems of systems in linking value chains.</p>
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615 KiB  
Article
A Measure of the Non-Determinacy of a Dynamic Neighborhood Model
by Anatoliy Shmyrin and Irina Sedykh
Systems 2017, 5(4), 49; https://doi.org/10.3390/systems5040049 - 12 Oct 2017
Cited by 1 | Viewed by 5821
Abstract
In this paper we define a non-deterministic dynamic neighborhood model. As a special case, a linear neighborhood model is considered. When a non-deterministic neighborhood model functions, it is possible to introduce a restriction on the number of active layers, which will allow the [...] Read more.
In this paper we define a non-deterministic dynamic neighborhood model. As a special case, a linear neighborhood model is considered. When a non-deterministic neighborhood model functions, it is possible to introduce a restriction on the number of active layers, which will allow the variation of the non-determinism of the model at each moment of time. We give the notion of the non-determinacy measure and prove that it has the properties of a probability measure. We formulate the problem of reachability with partially specified parameters, layer priorities, and the non-determinacy measure. An algorithm for solving the attainability problem for a neighborhood model with variable indeterminacy and layer priorities is presented. An example of its solution is shown, which shows that when the priorities are compared and the measure of non-determinism is used, the solution of the problem can be obtained more quickly than by a method that does not use priorities. Full article
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<p>Neighborhood model structure: (<b>a</b>) first layer; (<b>b</b>) second layer; (<b>c</b>) third layer.</p>
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<p>The state tree for the neighborhood model in <a href="#systems-05-00049-f001" class="html-fig">Figure 1</a>, taking into account the priorities.</p>
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1394 KiB  
Article
Packageability as an ‘Ility’ for Systems Engineering
by Rick L. Sturdivant and Edwin K. P. Chong
Systems 2017, 5(4), 48; https://doi.org/10.3390/systems5040048 - 23 Sep 2017
Viewed by 8459
Abstract
The usefulness of packageability as one of the ‘ilities’ for systems engineering was investigated. It was found that packageability plays an important role in a multitude of systems, and it was investigated in several ways. First, a brief analysis showed that at least [...] Read more.
The usefulness of packageability as one of the ‘ilities’ for systems engineering was investigated. It was found that packageability plays an important role in a multitude of systems, and it was investigated in several ways. First, a brief analysis showed that at least two criteria must be met for something to be considered an ility. These criteria are that the ility often manifests itself after the system is deployed, and that the potential ility must not simply be a persistent physical characteristic. It was shown that packageability meets both requirements. Second, six different systems were examined, revealing nine general ways packageability is used. They provide a way for system engineers to recognize packageability as a non-functional system property. The usefulness of packageability as a top-level non-functional system property is shown, as well as for sub-systems and components. A working definition of packageability is then proposed. Finally, a detailed treatment of packageability is presented for radar systems with transmit–receive modules. Packageability was shown to be a useful ility category that can add value to stakeholders, and that captures real system features that are not captured by other ilities. This work demonstrates that packageability should be considered as an ility for systems engineers. Full article
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<p>‘Ilities’ are useful as non-functional requirements at the system level and are translated into functional requirements deeper into the system to the parts level.</p>
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<p>Active Electronically Scanned Arrays (AESAs) are used on (<b>a</b>) F/A-18E/F Super Hornet with an AESA phased array located in the nose of the aircraft; and (<b>b</b>) Euroradar CAPTOR mounted onto the nose of a Eurofighter Typhoon aircraft.</p>
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<p>A transmit/receive (T/R) module has multiple competing requirements such as high frequency interconnects, heat dissipating integrated circuits, dissimilar materials, coupling between circuits, and module level resonances, which must all be balanced to achieve packageability.</p>
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